Improvement in saw-mill head-blocks



SAMUEL w. HARRIS.4

I' Improvement in Saw Mill He'ad Blocks.

415.120,514. Patented 0,01; 31,1811.

.dttorneg/s.

UNITED STATES PATENT QFFICE.

SAMUEL W. HARRIS, OFQJAMESTOWN, NEVV- YORK, ASSIGNOR TO HIMSELF AND JOSEPHUS H. CLARK, OF SAME PLAGE.

IMPROVEMENT IN SAW-MILL HEAD-BLOCKS.

Specification forming part of Letters Patent No. 120,514, dated October 31, 1871.

In order to enable others skilled in the art to Y which my invention appertains to make and use the same, Iwill now proceed to describe its construction and operation, referring to the annexed drawing, in which- Figure l is a plan view, and Fig. 2 a side view of my improved double-screw setworks. Fig. 3 shows a die used in the same 5 and Fig. 4 is a section of one of the operating levers.

A A represent metallic bail-blocks, of which there are two at each end of the carriage B. At the back end of each bail-block iswan arm, C, running toward the center, or, in other words, inward toward the other block at the saine end of the carriage. One of these arms at each end of the carriage has a longitudinal tongue, a., fitting in a corresponding groove on the other arm, which prevents the bail-blocks from twisting or binding on the screw D when moving back and forth on the same. The screw D is a rightandleft hand-screw, running the entire length of the head-block E, and passing through thebail-blocks A A. In the rear end of each bail-block, above and in rear of the screw, is an inclined mortise extending inward to the screw, for the reception of a self-adjusting die, G, which has a thread, b, on the end to fit the screw D. This die Gis constructed as shown in Fig. 3 that is, so as to fit the inclined morti se in the bail-block-and being on an incline above the scremits weight will adjust it to the same. The upper end ofthe die G is slotted, and in said slot is pivoted a short lever, H, having, if necessary, a weight, d, on its outer end. This lever is used to raise the die out of the screw D, as well as to hold it in its place when the screw 'is pressing against it. The lever is provided with an eccentric hook, e, near its pivot point, which hook catches under the upper part ofthe dieseat when the die is adjusted. The lever lifts the die Gr when thrown forward on the bail-block, and -prevents it from rising when thrown back. Upon the end of each screw D is a ratchet-wheel, I, and lever J, the lever being provided with a hand or pawl, f, to fit the wheel I. This hand is placed upon a pin on the side of the lever, and has on its inner side a pin, i, which ts in holes or notches made in the side of the lever-one when the hand is raised up and the other when the hand is on the wheel. The hand is held at either point by a coiled wire-spring, h, on the outer end of the pin the hand is on, the object being to prevent the hand from bounding over any cog, and to hold it up when it is oft' the wheel. The leverJ extends below the screw D and is attached to a short rod, K, running by the side of the carriage B and attaching to a clasp, 7c, which lits loosely over the upper part of a at iron rod, L. This rod runs the entire length of the carriage, or far enough to connect with the other block E in the same manner. The clasps 7c are fastened to the rod L, by means of set-screws, at any place desired, and the rod L is held to the carriage B by brackets m m, which, at the same time, allow it to slide lengthwise of the carriage. By thus connecting the bail-blocks at both ends of the carriage both ends of the log may be set at the same time, and by raising the hand off of one of the ratchet-wheels one end may be set and not the other. The front ends of the bail-blocks are locked to the log-plate by tongue and groove, as shown at x, Fig. 2, which prevents them from raising up at the front ends or rocking over the screw D.

These improvements may apply as well to oircular as to upright saws.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. The arms O C attached to the bail-blocks A A and matching each other, substantially as and for the purposes herein set forth.

2. The combination of the bail-block A, die G, with thread b, and the lever H with eccentric hook e, all constructed and arranged substan- In testimony that I claim the foregoing I have tially as and for the purposes herein set forth. hereunto set my hand this 23d day of August7 3. The Within-described double-screw set- 1871.

Works When all its parts are constructed, ar- SAMUEL W. HARRIS.

ranged, and combined to operate sulostantalbT Witnesses:

in the manner and for the purposes herein set LEVANT B. BROWN, l forth. F. B. WHITGOMB. (130) 

